Patent classifications
G01R33/3858
PERMANENT MAGNET ASSEMBLY FOR MAGNETIC RESONANCE IMAGING WITH NON-FERROMAGNETIC FRAME
An assembly for providing a B.sub.0 magnetic field for a magnetic resonance imaging (MRI) system, the assembly comprising: a plurality of rods extending along a common longitudinal direction and positioned to form a bore extending along the common longitudinal direction, the plurality of rods including a first rod, the first rod comprising: ferromagnetic segments, each having a net magnetization in a plane that is substantially perpendicular to the common longitudinal direction; and non-ferromagnetic segments.
PERMANENT MAGNET ASSEMBLY FOR MAGNETIC RESONANCE IMAGING WITH NON-FERROMAGNETIC FRAME
An assembly for providing a B.sub.0 magnetic field for a magnetic resonance imaging (MRI) system, the assembly comprising: a plurality of ferromagnetic segments positioned to form: a bore extending along a common longitudinal direction, and a first gap, on a first side of the bore, to accommodate at least one first gradient coil, wherein at least some of the plurality of ferromagnetic segments are positioned on one side of the first gap and at least some others of the plurality of ferromagnetic segments are positioned on another side of the first gap.
MAGNETIC RESONANCE IMAGING SYSTEM WITH A ROTATABLE MAGNET
A magnetic resonance imaging system can include a magnetic field generator, an image acquisition region and a radiofrequency system including at least one radiofrequency antenna. The radiofrequency system can emit a radiofrequency excitation pulse into the image acquisition region and receive magnetic resonance signals from the image acquisition region. The magnetic field generator can include at least one magnet to generate a magnetic field in the image acquisition region, a magnet holder to carry the at least one magnet and a rotation system to position the magnet holder along a rotation trajectory.
SELF-SHIELDED SPLIT GRADIENT COIL
Gradient coil assemblies for horizontal magnetic resonance imaging systems (MRIs) and methods of their manufacture. Some embodiments may be used with open MRIs and can be used with an instrument placed in the gap of the MRI. In general, concentrations of conductors or radially oriented conductors may be moved away from the gap of the MRI so as to reduce eddy currents that may be induced in any instrument placed within the gap. Systems for directly cooling primary gradient and shield coils may be utilized and various coil supporting structures may be used to assist in coil alignment or to facilitate use of an instrument in the MRI gap.
Gradient system with controlled cooling in the individual gradient channels
A gradient coil system for a magnetic resonance imaging system includes a plurality of gradient coils for applying a gradient magnetic field to a target volume; at least one coolant tube per gradient coil for cooling the gradient coil (110A-C, 210A-C). The coolant tubes are connected to respective flow control devices and a controller, which is configured to control each flow control device of the flow control devices for adjusting the flow of a coolant in the respective coolant tube. The controller is configured to control the flow control device on the basis of heat load caused by the respective gradient coil.
PORTABLE NMR PROBE AND NMR APPARATUS
A portable NMR probe for the analysis of dispersions, the portable NMR probe comprising: a base part; a detachable probe assembly detachably mounted on the base part and electrically connected to the base part, the detachable probe assembly comprising: a housing; and a radio-frequency coil assembly received in the housing, the radio-frequency coil assembly comprising an RF coil support that has a channel for receiving an NMR sample, and an RF coil wound around the RF coil support for transmitting radio-frequency pulses to the NMR sample and for detecting magnetic resonance responses from the NMR sample; and a field magnet arranged to generate a magnetic field in the detachable probe assembly.
Cooling a gradient coil of a magnetic resonance imaging system
A gradient coil assembly of a magnetic resonance imaging system includes at least one gradient coil, a cooling arrangement for cooling the gradient coil, and an RF shield. The cooling arrangement includes at least one cooling tube that is configured to transport a cooling fluid and which is disposed on and in thermal contact with the gradient coil, wherein the assembly further comprises a thermal connector arrangement with at least one of a first thermal connector disposed between the RF shield and the at least one cooling tube, which provides a radially extending connection between the RF shield and the at least one cooling tube.
Supporting structure for a gradient coil assembly of a MRI
A gradient coil assembly (62) for use in a Magnetic Resonance Imaging (MRI) system includes primary coils (68), shield coils (72) and a supporting structure (10) arranged between the primary coils (68) and the shield coils (72). The supporting structure (10) includes at least a supporting element (12) including a first end face (14) and at least a first recess (24) with an opening (26) in the first end face (14). The first recess (24) extends in a longitudinal direction (18) of the supporting element (12) forming a tray for receiving a passive shim bar.
Gradient coil
A gradient coil according to an embodiment is configured to generate gradient magnetic fields along a plurality of axes in an imaging space in which a subject is imaged. The gradient coil includes a coil corresponding to at least one of the plurality of axes, wherein an electrically-conductive member of the coil is formed so as to be partitioned in a thickness direction by a plurality of electrically-insulative layers.
Nuclear magnetic resonance diffraction
In a general aspect, a magnetic resonance system includes a primary magnet system configured to generate a principal magnetic field in a sample region. The magnetic resonance system also includes a field source device. The field source device includes a substrate and first and second conductor layers on the substrate. The first conductor layer includes a constriction configured to generate a radio frequency magnetic field in the sample region. The second conductor layer is vertically centered above the first conductor layer, and includes gradient coils configured to generate first, second, and third magnetic field gradients along respective first, second and third mutually-orthogonal spatial dimensions in the sample region.